They confirmed that a farm worker in Lleida was infected with swine flu

After confirming a case of human infection with swine flu in Catalonia, experts pointed out that such incidents happen from time to time, so the true incidence of pig virus transmission to humans is unknown and a maximum surveillance system is needed to minimize the chance. A new epidemic.

The European Center for Disease Prevention and Control (ECDC) reported a case swine flu infection A worker at a farm in Lleida was infected with the virus. No further cases have been detected in the region and he is in good health after falling ill.Ministry of Health advice Influenza vaccination for people who work on farms, poultry or pig operations or come into contact with wild animals.

The Spanish authorities reported the infection on January 29 and published it in the corresponding ECDC bulletin for the week of January 28 to February 3.After diagnosis bronchitis, has been confirmed as swine influenza A (H1N1 subtype). The patient has fully recovered and no new cases have been identified among close contacts or farm colleagues. This will remain an isolated case.

The last similar case in Spain occurred in 2022, in a person from Navarre who also had contact with infected pigs. Since 2011, there have been reports that 19 cases in Europe and 73 cases globally.

Infections of swine influenza viruses into humans or vice versa are relatively common among people who come into contact with infected animals. As long as we remain alert to the possible emergence of new “recombinant” viruses, or new viruses with mutations, it should not become a social alarm. “That’s why it’s important to remain vigilant,” he explained. María Montoya, researcher in the Viral Immunology: Therapeutics and Vaccines Group of the Margarita Salas Biological Research Center (CIB-CSIC).

The natural host of influenza virus is flying birds.Different influenza viruses can infect birds and mammals, including humans and pigs, but they also infect sea ​​lion, seal, horse or dogOthers recalled this expert on the Science Media Center (SMC) platform.

Risk of genetic recombination

this flu virus Viruses that infect humans and pigs often have many similarities They can jump from humans to pigs easily. In fact, human influenza viruses are present in pig farms. People who have high contact with these animals, such as farm workers, can spread the virus to the animals and become infected with influenza viruses carried by pigs. Actually, The first pandemic virus of the 21st century was swine flu virusH1N1.

The risk to the community is the same as for circulating influenza viruses. Problems arise when a pig or human virus recombines with another influenza virus.. With this comes the emergence of new viruses, such as the H1N1 influenza virus in 2009. To prevent community risks, the most important thing is to conduct epidemiological surveillance on farms and people who are exposed to sick animals. In this way, necessary measures can be taken to protect animals and humans.

Swine influenza viruses typically circulate among pig herds. It can be spread sporadically to humans, mainly those who come into direct contact with animals. It cannot be spread by eating pork products, so there is no risk of food infection. When this jump occurs, it typically doesn’t spread from person to person; he noted that the virus has a lower ability to spread from person to person, and symptoms are usually milder or similar to the common flu, which is why The reason why it is often overlooked. José Ignacio Núñez and Llilianne Ganges, researchers at the Institute of Agricultural and Food Research and Technology (IRTA)

Another different case is 2009 pandemic influenza A (H1N1) virus. The virus, which contains fragments of avian, human and swine viruses, jumped to humans, causing the pandemic. It is distributed globally and humans have spread it to pigs. “In 2021, a Chinese organization published a scientific article identifying a virus circulating in pigs that had pandemic potential, but no outbreaks in humans have since been reported. Regardless, understanding these viruses is critical. In Swine are circulated through the herd to analyze their genomes.

“Influenza A, or swine flu, is prevalent around the world and in Spain, Europe’s main pig producer, there are up to four different subtypes of the virus: H1N1, H1N2, H3N1 and H3N2. There is a certain affinity between swine viruses. Swine flu and human flu have, in fact, been subject to well-documented transmission of each other for as long as this infectious disease has been known. This infectious promiscuity shows up when the genetic makeup of different human and swine flu viruses is analyzed. It just became obvious,” he added. Gustavo del Real, researcher at the National Institute of Agricultural and Food Research and Technology (INIA-CSIC).

“In any case, this specific case is a new warning that it is entirely possible, rather than unlikely, to introduce stable New swine flu strainThere is a risk of causing new pandemics in the human population, such as the one that occurred in 2009, either directly or through its combination with human strains. Therefore, it is necessary to implement specially designed epidemiological surveillance programs to detect this type of zoonotic disease immediately.To be able to stop and/or prevent outbreaks leading to An epidemic or epidemic with incalculable consequences“.

• Is it possible that more cases will emerge?

Not necessarily; humans may occasionally become infected with swine influenza viruses transmitted by pig farms, but this is uncommon. Similarly, people who come into contact with animals must also take biosecurity measures, and it is recommended to receive influenza vaccination to reduce the probability of infection. On the other hand, the ability to spread from person to person is very small.

• What risks exist to the community?

Since the ability to transmit from person to person is low, it does not pose a special risk. Symptoms range from mild to common flu, so it is not expected to be a problem.

• Are these cases of human infection with the H1N1 virus common?

Pandemic A(H1N1) viruses have been circulating seasonally in humans and globally since their emergence in 2009. Subsequently, humans transmitted the virus to pigs, and the virus also spread among pigs, now mainly with common pig subtypes.